A slide-fastener stringer half is known, having a support tape which is formed of warp-knitted goods having wales running longitudinally of the tape and courses extending transversely. Each wale is the product of a respective needle of the knitting machine, even though at times the wales do not represent ridges or formations on the surface but are smooth therewith. Customarily such an arrangement is made with warp yarns by which is meant filaments extending mainly longidudinally, that form respective chains of loops or pillars extendng longitudinally of the fabric, and of weft filaments which extend mainly transversely, being laid into the chains of loops being formed by the warp filaments.
In the known tapes (see especially German open application DT-OS 2,016,141 and U.S. Pat. No. 3,708,836) the weft filaments are laid in over four needles, or over four wales of the tape so as to give this tape good transverse dimensional stability and to improve the longitudinal dimensional stability mainly determined by the warp yarns.
More particularly, in this arrangement the wales are of the single-bar type formed as warp chains which are bridged only by the filler or weft. As indicated the sole connecting threads or yarns between the warp chains are the laid-in weft filaments or yarns which extend over four warp chains each so that four such weft inlays fill each warp loop to provide the transverse stability of the tape (stability in the plane of the tape perpendicular to the warp chains) and, in addition, prevent longitudinal extension and contraction (change of dimension in the plane of the tape parallel to the warp chains). The dimensional stability is most pronounced if the tapes are composed of synthetic-resin yarn which has been thermofixed, i.e. subjected to a heating or ultrasonic treatment which relaxes internal stresses within the yarn.
The advantage of single-bar warp chains, i.e. individual spaced apart wales of loops interconnected only by the weft, is that channels are formed between wales so that the row of stitching for attaching the coupling element can lay along one of these channels or valleys.
Needle patterns are typically used in the needle art wherein the needles are so set up as if it was never the same needle, but as if the necessary new needle row for the formation of another stitch row always lay above the preceding row. This described system is, however, not as efficient as could be desired, since the support tapes for such slide-fastener stringer halves are not made by using the full capacity of modern knitting machines. Further, although stitching along between a pair of wales to attach the coupling element does not pose a problem, it is desirable to improve the stitching speed.